The present invention relates mainly to a current comparator circuit suitable for use in various types of electronic apparatus, and particularly to a current comparator circuit capable of low power or low voltage driving.
Comparator circuits which have been used in various kinds of electronic apparatus perform a comparison mostly on the basis of voltage, in which voltage V.sub.S of a supplied input signal is compared with a reference voltage to obtain some detected voltage. In such a comparator circuit as to make a comparison on the basis of voltage, a power source voltage for obtaining the reference voltage requires something in addition to the voltage V.sub.S of the input signal. As a result, when the voltage V.sub.S of the input signal is large, the source voltage should be made high resulting in the increase of electric power. Therefore, there is a limit to low power or low voltage driving and high frequency driving.